给定一个只含非负整数的m*n网格,找到一条从左上角到右下角的可以使数字和最小的路径。
样例
注意
你在同一时间只能向下或者向右移动一步
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| public class Solution { * @param grid: a list of lists of integers. * @return: An integer, minimizes the sum of all numbers along its path */ public int minPathSum(int[][] grid) { if(null == grid) return 0; int row = grid.length; int col = grid[0].length; if(row <= 0 || col <= 0) return 0; int[][] steps = new int[row][col]; steps[0][0] = grid[0][0]; for(int i = 1;i < row;i++) { steps[i][0] += steps[i - 1][0] + grid[i][0]; } for(int i = 1;i < col;i++) { steps[0][i] += steps[0][i - 1] + grid[0][i]; } for(int i = 1;i < row;i++) { for(int j = 1;j < col;j++) { steps[i][j] = Math.min(steps[i - 1][j], steps[i][j - 1]) + grid[i][j]; } } return steps[row - 1][col - 1]; } }
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